1. Technical Field
This invention relates to a wireless foot controller that may be used to control devices including medical devices.
2. Description of the Prior Art
Many applications can benefit from hands-free control, and in particular, many surgical applications can benefit by allowing control of surgical instruments without requiring the instruments' operators to use their hands to control the instruments. There have been several applications in the prior art that use footswitches or foot pedals to control surgical instruments. However, many of these applications use wired connections between the controller and the controlled device. This hardwired arrangement suffers many problems, however, including requiring multiple controllers to control multiple devices, safety hazards from floor to table wiring, and requiring additional effort to maintain a sterile environment.
To address these problems, some applications offer wireless control of devices. For example, U.S. Pat. No. 7,428,439 (Reynolds et al.) describes a wireless foot control system using infrared signaling between the transmitter and the receiver in the controlled device. However, infrared signaling can be problematic because it typically requires the transmitter to be within the line of sight of the receiver or at least requires particular arrangements of the transmitter and receiver that may be inconvenient in practice.
Other wireless foot controllers use radiofrequency signaling, which does not require a line of sight arrangement between the transmitter and receiver. However, these applications frequently suffer from interference from other radiofrequency-emitting devices and thus tend to have problems associating (i.e., bonding or syncing) the controller with a controlled device, particularly where a single controller is used to control multiple devices. One attempt to overcome this problem is described in U.S. Patent Application Publication No. 2007/0249286 (Ma et al.), which describes a system and method for associating a wireless transmitter to multiple wireless devices. But this application requires first establishing a wired connection to each of the controlled devices in order to associate the device with the controller. This extra step of physically connecting the device to the controller is inconvenient and may compromise the sterility of a controlled surgical instrument. U.S. Patent Application Publication No. 2008/0140158 (Hamel et al.) describes a wireless foot controller capable of controlling multiple devices using the Bluetooth or IEEE 802.11a, b, g, 802.12 or 802.16 wireless standards. However, this approach also suffers from problems associating the controlled device with the controller, and typically requires bringing each controlled device into close proximity to the controller in order to associate (“sync”) the controlled device with the controller. As with the wired association solution, this approach is inconvenient and may compromise the sterility of a controlled surgical instrument.
Thus there exists a need in the art for a wireless foot controller capable of controlling multiple devices, and capable of associating with controlled devices without requiring a physical connection or close physical proximity between the controller and the controlled devices.